Iwatsu ENTERPROSE-CS Owner's Manual page 204

Key Lamp Indication for Day-1, Day-2, Day-3, and Night Mode
The System Night Mode key will change the LED lamp status based on the
System Ringing mode. The LED lamp indication is reflected for the ringing
mode on all Iwatsu telephones (legacy and ICON Series) with a Night Mode
key.
 Day-1 Ringing Mode = No lamp indication.
 Day-2 Ringing Mode = Slow red flash.
 Day-3 Ringing Mode = Fast red flash.
 Night Ringing Mode = Solid red flash.
Note: Iwatsu ICON Series Self-Labeling Key name change is not supported
with the Multiple Ringing Mode.
Group Ringing Mode (Group Night) Operation
When the ECS system is in the Group Ringing Mode (default = System
Ringing Mode), pressing the existing Group Night Mode key (Trunk Groups
001-250) from an Iwatsu ICON Series telephone (5810, 5910 and 5930)
attendant position will take you to the Select Ringing Mode screen
 The key operation for the Group Night Mode key with the Group
parameter can only toggle between Day / Night Modes if assigned on
any legacy telephone, the Attendant Console, or ICON Series 5800 /
5900
 Group Night Mode key assigned to the self labeling key will indicate
current ringing mode as shown below:
To change the ringing mode from an ICON Series Attendant
Position
TGNNN Day-1 indicates Day-1 mode, TGNNN Ring-Day2 indicates Day-2
mode, TGNNN Ring-Day3 indicates Day-3 mode and TGNNN Night
indicates Night mode. *NNN is Trunk Group Number 1-250.
If database programming in Trunks > IPNET/PRI Trunk Group Data >NSF
Ringing-ISDN > Group Name (Class 29.02) has a name assigned, the key will
indicate first 11 characters of the name instead.
ATTENDANT POSITION USER GUIDE - 186